Piston noise

Hello,

after 30mm of ride when the engine is hot i can hear a fiction from the first piston.
The spark plug is wet and black. I have white smoke from the exhaust particulary at starting.

Just the rings to replace or overbore ?

What do you think ?

Thank you
Fox

Could it just be a fouled plug?  

I ever try an other carb or other plug ... always that sound when the engine is hot

I would suggest you need to get in and have a look, before you can decide "rings or re-bore" you need to measure up. However if there is mechanical noise I would investigate sooner rather than later to avoid possible terminal damage (is there any metal in the oil?)

I think it's time to check compression.